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Stormwater Control Report - Sept '16 eck) ENVIRONMENTAL DESIGN PARTNERSHIP, LLP STORMWATER CONTROL REPORT PROPOSED SINGLE FAMILY HOME FOR MICHAEL FEENEY TOWN OF BOLTON, NEW YORK Prepared For: Michael Feeney Prepared By: THE ENVIRONMENTAL DESIGN PARTNERSHIP 900 Route 146 Clifton Park, NY 12065 Date: September 2016 900 Route 146, Clifton Park, New York 12065 phone(518)371-7621 - fax(518)371-9540 edo 1. INTRODUCTION: The applicant is proposing the development of an existing 5.06+/- acre parcel located along the western side of Lockhart Mountain Road in the Town of Queensbury, New York. The proposed development shall consist of the construction of a new driveway and the construction of a single family dwelling. The area of proposed disturbance is on the order of 65,400 square feet which exceeds a 15,000 square feet threshold and therefore is defined as a Major Project by the Chapter 147 of the Queensbury Town Code. The objective of this report is to describe the storm water facilities to be constructed as part of the proposed development and verify their adequacy for compliance with Chapter 147 of the Queensbury Town Code. 2. TECHNICAL REFERENCE Applied Microcomputer Systems' program Hydrocad was used to model the detailed characteristics of the watershed and hydraulics of the stormwater management facilities. Hydrocad employs The United States Department of Agriculture's Soil Conservation Service (SCS) Technical Release 20 (TR-20). TR-20 is the benchmark hydraulic method for computation of storm volumes and peak runoff. It is in full compliance with the methodologies specified in Town Stormwater Management Regulations. Full results are included for the 10 and 25 year, 24 hour design storm events 3. EXISTING CONDITIONS: The site currently is wooded with the existing topography of the land in the area of the proposed development generally varies between 10% and 25% and sloping east toward the existing wetlands and stream on the property. The USDA Natural Resources Conservation Service soil survey shows the soils on the site to be Charlton fine sandy loam which is a well-drained soil classified as Hydrologic Soil Group "B" and Massena fine sandy loam which are poorly drained soils classified as Hydrologic Soil Group "C". Test pits performed on the site in June 2016 showed a sandy loam with groundwater/bedrock greater than 7 feet below grade. The soils observed throughout are site are consistent with Hydrologic Soil Group "B". A hydraulic model of the existing site was prepared using the Hydrocad program. One subcatchment was used to represent the existing drainage characteristics, see figure 2. The existing parameters of topography, vegetation, slope and soil type are all incorporated into the predevelopment hydraulic model. The results for the existing condition model are summarized later in this report and have been included in Appendix A. 2 900 Route 146, Clifton Park, New York 12065 phone(518)371-7621 - fax(518)371-9540 edo 4. POSTDEVELOPMENT Development of the property will consist of the construction the single family home and construction of a new driveway. Stormwater management practices have been designed to attenuate and infiltrate the stormwater runoff from the proposed impervious surfaces on the site. The proposed stormwater management shall consist of three shallow grassed swales located throughout the proposed site to collect and infiltrate the stormwater runoff from the proposed driveway and upgradiant areas. A stone eave trench and a stone infiltration trench are also proposed to attenuate and infiltrate the stormwater runoff from the proposed house roof. The shallow grassed swales and stone trenches have been sized accordingly to allow for complete attenuation and infiltration of the contributing stormwater runoff from storms up to the 25 year design storm event. Any outfalls from the shallow grassed swales will be directed either toward the driveway swales and the existing wetlands/stream located on the site. The post-development conditions were modeled using the Hydrocad program. Seven Subcatchments were used to represent the proposed drainage characteristics, see figure 3. A curve number (CN) of 61 was used for all grassed areas and a CN of 98 was used for all pavement areas. The results of the post-development modeling have been summarized in the following subsections and included in Appendix B. 4.1. Town of Queensbury Stormwater Regulations The proposed project will consist of greater than 15,000 square feet of disturbance and therefore, according the Chapter 147 of the town code, is considered a major project. The proposed stormwater management has been designed in accordance with the Queensbury Town Code which mandates that the volume of runoff for a ten year storm must be maintained after development and that the peak rate of runoff must not be increased for the 25 year storm. Since the project will not disturb greater than 5 acres the stormwater management does not need to be designed to attenuate the runoff from a 100 year storm event. The following tables summarize the stormwater modeling results. 3 900 Route 146, Clifton Park, New York 12065 phone(518)371-7621 - fax(518)371-9540 edo Table 1: 10-Year Storm Runoff Volume Storm Event Predevelopment Runoff Post-Development Runoff Volume (ac-ft) Volume (ac-ft) 10-Year, 3.8" 0.195 0.080 Table 2: 25-Year Storm Runoff Rate Storm Event Predevelopment Runoff Post-Development Runoff Rate cfs Rate cfs 25-Year, 4.3" 3.30 2.76 5. SUMMARY Due to development of the project site there will be a need for stormwater management. In order to attenuate and infiltrate the increased runoff, shallow grassed swales have been designed. The stormwater management for the proposed site has been designed in accordance with Chapter 147 of the Queensbury Town Code. Upon proper construction and maintenance of the storm facilities detailed on the plans, the proposed construction will have no significant adverse impacts on downstream properties and water bodies. Prepared by: AIII ' Brandon Ferguson, P.E. 4 900 Route 146, Clifton Park, New York 12065 phone(518)371-7621 - fax(518)371-9540 edo REFERENCES: HydroCAD version 8.50, Applied Microcomputer Systems, Chocura, New Hampshire. Rawls, W.J., Brakensiek, D.L., and Saxton, K. E., 1982. "Estimation of Soil Properties", Transactions of the American Society of Agricultural Engineers, Vol. 25, No. J, pp. 1316-1320. S.C.S., 1982. "TR-20 Project Formulation-Hydrology, Technical Release No. 20", U.S. Department of Agriculture, Soil Conservation Service, Hydrology Unit Division of Engineering. Town of Lake George, July 2003."Chaper 175-21, Erosion, sedimentation and stormwater runoff control", Code of the Town of Lake George. United States Department of Agruculture, N.R.C.S. Web Soil Survey, http://websoiIsurvey.nres.usda.gov/app/Web Soil Survey.aspx 5 900 Route 146, Clifton Park, New York 12065 phone(518)371-7621 - fax(518)371-9540 rd, f / �§ �r �i y //'' r l� rf " �vO,,i i i r �M M � t✓.�"� %,,,, / ''mow /lrr rr SITE LOCATIONAi ryf r J ,j Alolwo " q /I J T ias 01 Ay te if s f 1 // /%/"J���1�� ff r✓rYr�W'17J�����1� l�O J��//���� /J , I l / �� / r� ���//���/° rel/ j'6 %% / //l% % /�,i R .,;Jig// � D Figure 1: Site Location 9NIA3Amns ONtlI amn.Loaamomv 3dVOSONVI 9NIL33NION3 LZ9L-LL£(8LS) 99OZL 'A'N `MMVd NO1d177 9bL 3jLnom d77 `dlHSM3N.LMVd N91S34 'lV1N3WN0HIAN3 'ON 3af1013 9ioz '6i maKudas )MOA M3N ')UNnOO NagHYM AxnasN33nb 30 NMod, M 31va SNOISIMa A-RNHHd rlHATH D I W 2KdOrlaA2I S iN��aoz�n�a�xa =:3-lVOS d0 SQNV'I 210d NV'Id d,LIS QdSOdMld 31111133HS o arvoy AIIVLNf]ON L276H31J07 rz W UZ U �J i i L_ ON —— 9NIA3Amns ONtlI 3LI11oaamomv 3dVOSONVI 9NIL33NION3 LZ9L-LL£(8LS) 99OZL 'A'N `MMVd NO1d177 9bL 3jLnom d77 `dlHSM3N.LMVd N91S34 7V1N3WN0HIAN3 'ON 3af1013 9ioz '6i maKudas )MOA M3N ')UNnOO NagHYM AxnasN33nb 30 NMod, M 31va SNOISIMa A-RNHHd rlHATH D I W 2KdOrlaA2I S iN��aoz�n�a�xa =:3-lVOS L40 SQNV'I 210d NV'Id d,LIS QdSOdMld 31111133HS QV02I NdIVLN DOIf L276HX)07 a dim � N o 0 3� (n t M 6t. S a a a a N N } r t Appendix A Predevelopment Stormwater Modeling Results is ) (2S ) C CULVERT Dn1 DESIGN POINT Subcat Reach on Link Drainage Diagram for PREDEVELOPMENT Prepared by{enter your company name here}, Printed 9/14/2016 HydroCAD®8.50 s/n 000476 ©2007 Hydro CAD Software Solutions LLC PREDEVELOPMENT Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 5.037 60 Woods, Fair, HSG B (1S,2S) 0.005 98 (is) 0.020 98 ROAD (2S) 5.062 TOTAL AREA PREDEVELOPMENT Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (acres) Goup Numbers 0.000 HSG A 5.037 HSG B 1 S, 2S 0.000 HSG C 0.000 HSG D 0.025 Other 1 S, 2S 5.062 TOTAL AREA PREDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 4 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Runoff Area=194,460 sf 0.11% Imperious Runoff Depth>0.46" Flow Length=860' Tc=15.4 min CN=60 Runoff=2.20 cfs 0.170 of Subcatchment2S: Runoff Area=26,060 sf 3.34% Imperious Runoff Depth>0.50" Flow Length=330' Tc=12.5 min CN=61 Runoff=0.37 cfs 0.025 of Reach C: CULVERT Avg. Depth=0.70' Max Vel=3.73 fps Inflow=2.20 cfs 0.170 of D=12.0" n=0.025 L=27.0' S=0.0200 '/' Capacity=2.62 cfs Outflow=2.19 cfs 0.170 of Link D: DESIGN POINT Inflow=2.53 cfs 0.195 of Primary=2.53 cfs 0.195 of Total Runoff Area = 5.062 ac Runoff Volume = 0.195 of Average Runoff Depth = 0.46" 99.51% Pervious = 5.037 ac 0.49% Impervious = 0.025 ac PREDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: Runoff = 2.20 cfs @ 12.11 hrs, Volume= 0.170 af, Depth> 0.46" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 194,240 60 Woods, Fair, HSG B 220 98 194,460 60 Weighted Average 194,240 Pervious Area 220 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 6.5 760 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 15.4 860 Total Summary for Subcatchment 2S: Runoff = 0.37 cfs @ 12.07 hrs, Volume= 0.025 af, Depth> 0.50" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 25,190 60 Woods, Fair, HSG B 870 98 ROAD 26,060 61 Weighted Average 25,190 Pervious Area 870 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.1600 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 2.4 230 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.5 330 Total Summary for Reach C: CULVERT Inflow Area = 4.464 ac, 0.11% Impervious, Inflow Depth > 0.46" for 10 YEAR event Inflow = 2.20 cfs @ 12.11 hrs, Volume= 0.170 of Outflow = 2.19 cfs @ 12.12 hrs, Volume= 0.170 af, Atten= 0%, Lag= 0.2 min PREDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 6 Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 3.73 fps, Min. Travel Time= 0.1 min Avg. Velocity = 1.93 fps, Avg. Travel Time= 0.2 min Peak Storage= 16 cf @ 12.11 hrs, Average Depth at Peak Storage= 0.70' Bank-Full Depth= 1.00', Capacity at Bank-Full= 2.62 cfs 12.0" Diameter Pipe, n= 0.025 Corrugated metal Length= 27.0' Slope= 0.02007' Inlet Invert= 131.61', Outlet Invert= 131.07' Summary for Link D: DESIGN POINT Inflow Area = 5.062 ac, 0.49% Impervious, Inflow Depth > 0.46" for 10 YEAR event Inflow = 2.53 cfs @ 12.11 hrs, Volume= 0.195 of Primary = 2.53 cfs @ 12.11 hrs, Volume= 0.195 af, Atten= 0%, Lag= 0.0 min Primary outflow= Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs PREDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 7 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Runoff Area=194,460 sf 0.11% Imperious Runoff Depth>0.76" Flow Length=860' Tc=15.4 min CN=60 Runoff=4.14 cfs 0.281 of Subcatchment2S: Runoff Area=26,060 sf 3.34% Imperious Runoff Depth>0.81" Flow Length=330' Tc=12.5 min CN=61 Runoff=0.68 cfs 0.040 of Reach C: CULVERT Avg. Depth=1.00' Max Vel=3.80 fps Inflow=4.14 cfs 0.281 of D=12.0" n=0.025 L=27.0' S=0.0200 '/' Capacity=2.62 cfs Outflow=2.62 cfs 0.281 of Link D: DESIGN POINT Inflow=3.30 cfs 0.321 of Primary=3.30 cfs 0.321 of Total Runoff Area = 5.062 ac Runoff Volume = 0.321 of Average Runoff Depth = 0.76" 99.51% Pervious = 5.037 ac 0.49% Impervious = 0.025 ac PREDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 1S: Runoff = 4.14 cfs @ 12.10 hrs, Volume= 0.281 af, Depth> 0.76" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 194,240 60 Woods, Fair, HSG B 220 98 194,460 60 Weighted Average 194,240 Pervious Area 220 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 6.5 760 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 15.4 860 Total Summary for Subcatchment 2S: Runoff = 0.68 cfs @ 12.06 hrs, Volume= 0.040 af, Depth> 0.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 25,190 60 Woods, Fair, HSG B 870 98 ROAD 26,060 61 Weighted Average 25,190 Pervious Area 870 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.1600 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 2.4 230 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.5 330 Total Summary for Reach C: CULVERT Inflow Area = 4.464 ac, 0.11% Impervious, Inflow Depth > 0.76" for 25 YEAR event Inflow = 4.14 cfs @ 12.10 hrs, Volume= 0.281 of Outflow = 2.62 cfs @ 12.10 hrs, Volume= 0.281 af, Atten= 37%, Lag= 0.0 min PREDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 9 Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 3.80 fps, Min. Travel Time= 0.1 min Avg. Velocity = 2.15 fps, Avg. Travel Time= 0.2 min Peak Storage= 21 cf @ 12.05 hrs, Average Depth at Peak Storage= 1.00' Bank-Full Depth= 1.00', Capacity at Bank-Full= 2.62 cfs 12.0" Diameter Pipe, n= 0.025 Corrugated metal Length= 27.0' Slope= 0.02007' Inlet Invert= 131.61', Outlet Invert= 131.07' Summary for Link D: DESIGN POINT Inflow Area = 5.062 ac, 0.49% Impervious, Inflow Depth > 0.76" for 25 YEAR event Inflow = 3.30 cfs @ 12.07 hrs, Volume= 0.321 of Primary = 3.30 cfs @ 12.07 hrs, Volume= 0.321 af, Atten= 0%, Lag= 0.0 min Primary outflow= Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Appendix B Post-development Stormwater Modeling Results 4S 5S 6S 3S 2P 4P S LLOW GRASS EAVE TRENCH 5P 1 P 2S INFILTRATION is � TRENCH SHAL OW GRASS 3P SHALL W GRASS C 7S CULVERT DDj DESIGN POINT Subcat Reach on Unkl Drainage Diagram for POSTDEVELOPMENT Prepared by{enter your company name here}, Printed 9/14/2016 HydroCAD®8.50 s/n 000476 ©2007 Hydro CAD Software Solutions LLC POSTDEVELOPMENT Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 3.546 60 Woods, Fair, HSG B (1S,2S,3S,4S,7S) 1.203 61 >75% Grass cover, Good, HSG B (1 S,2S,3S,4S,6S,7S) 0.216 98 DRIVE (1 S,2S,3S,4S,7S) 0.025 98 ROAD (1 S,7S) 0.070 98 ROOF (5S,6S) 5.061 TOTAL AREA POSTDEVELOPMENT Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (acres) Goup Numbers 0.000 HSG A 4.749 HSG B 1 S, 2S, 3S, 4S, 6S, 7S 0.000 HSG C 0.000 HSG D 0.312 Other 1 S, 2S, 3S, 4S, 5S, 6S, 7S 5.061 TOTAL AREA POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 4 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: Runoff Area=60,990sf 2.72% Impervious Runoff Depth>0.50" Flow Length=500' Tc=13.9 min CN=61 Runoff=0.82 cfs 0.058 of Subcatchment2S: Runoff Area=112,830 sf 0.90% Imperious Runoff Depth>0.50" Flow Length=770' Tc=13.0 min CN=61 Runoff=1.57 cfs 0.107 of Subcatchment3S: Runoff Area=7,740 sf 26.49% Imperious Runoff Depth>0.96" Flow Length=155' Slope=0.1200 '/' Tc=0.6 min CN=71 Runoff=0.38 cfs 0.014 of Subcatchment4S: Runoff Area=17,840 sf 19.56% Imperious Runoff Depth>0.80" Flow Length=660' Tc=11.0 min CN=68 Runoff=0.51 cfs 0.027 of Subcatchment5S: Runoff Area=1,530 sf 100.00% Imperious Runoff Depth>3.02" Flow Length=20' Slope=0.4000 '/' Tc=0.1 min CN=98 Runoff=0.20 cfs 0.009 of Subcatchment6S: Runoff Area=2,320 sf 65.95% Imperious Runoff Depth>1.87" Flow Length=20' Slope=0.4000 '/' Tc=0.1 min CN=85 Runoff=0.22 cfs 0.008 of Subcatchment7S: Runoff Area=17.210 sf 13.48% Imperious Runoff Depth>0.66" Flow Length=230' Tc=11.3 min CN=65 Runoff=0.38 cfs 0.022 of Reach C: CULVERT Avg. Depth=0.18' Max Vel=4.75 fps Inflow=0.82 cfs 0.058 of D=36.0" n=0.012 L=27.0' S=0.0259 '/' Capacity=116.34 cfs Outflow=0.82 cfs 0.058 of Pond 1P: SHALLOW GRASS Peak Elev=149.25' Storage=159 cf Inflow=0.38 cfs 0.014 of Discarded=0.08 cfs 0.014 of Primary=0.00 cfs 0.000 of Outflow=0.08 cfs 0.014 of Pond 2P: SHALLOW GRASS Peak Elev=163.61' Storage=382 cf Inflow=0.51 cfs 0.027 of Discarded=0.08 cfs 0.027 of Primary=0.00 cfs 0.000 of Outflow=0.08 cfs 0.027 of Pond 3P: SHALLOW GRASS Peak Elev=147.47' Storage=1,711 cf Inflow=1.57 cfs 0.107 of Discarded=0.17 cfs 0.100 of Primary=0.00 cfs 0.000 of Outflow=0.17 cfs 0.100 of Pond 4P: EAVE TRENCH Peak EIev=206.30' Storage=121 cf Inflow=0.20 cfs 0.009 of Outflow=0.03 cfs 0.009 of Pond 5P: INFILTRATION TRENCH Peak EIev=196.32' Storage=123 cf Inflow=0.22 cfs 0.008 of Outflow=0.03 cfs 0.008 of Link D: DESIGN POINT Inflow=1.17 cfs 0.080 of Primary=1.17 cfs 0.080 of Total Runoff Area = 5.061 ac Runoff Volume = 0.245 of Average Runoff Depth = 0.58" 93.84% Pervious = 4.749 ac 6.16% Impervious = 0.312 ac POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: Runoff = 0.82 cfs @ 12.09 hrs, Volume= 0.058 af, Depth> 0.50" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 43,310 60 Woods, Fair, HSG B 1,330 98 DRIVE 330 98 ROAD 16,020 61 >75% Grass cover, Good, HSG B 60,990 61 Weighted Average 59,330 Pervious Area 1,660 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.1600 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 3.8 400 0.1200 1.73 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 13.9 500 Total Summary for Subcatchment 2S: Runoff = 1.57 cfs @ 12.08 hrs, Volume= 0.107 af, Depth> 0.50" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 92,090 60 Woods, Fair, HSG B 1,010 98 DRIVE 19,730 61 >75% Grass cover, Good, HSG B 112,830 61 Weighted Average 111,820 Pervious Area 1,010 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 3.8 470 0.1700 2.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.3 200 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 13.0 770 Total POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment 3S: Runoff = 0.38 cfs @ 11.90 hrs, Volume= 0.014 af, Depth> 0.96" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 2,050 98 DRIVE 1,210 60 Woods, Fair, HSG B 4,480 61 >75% Grass cover, Good, HSG B 7,740 71 Weighted Average 5,690 Pervious Area 2,050 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 75 0.1200 2.47 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" 0.1 80 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 0.6 155 Total Summary for Subcatchment 4S: Runoff = 0.51 cfs @ 12.04 hrs, Volume= 0.027 af, Depth> 0.80" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 5,890 60 Woods, Fair, HSG B 3,490 98 DRIVE 8,460 61 >75% Grass cover, Good, HSG B 17,840 68 Weighted Average 14,350 Pervious Area 3,490 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 1.7 240 0.2100 2.29 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.4 320 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 11.0 660 Total POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 5S: Runoff = 0.20 cfs @ 11.89 hrs, Volume= 0.009 af, Depth> 3.02" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 1,530 98 ROOF 1,530 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 20 0.4000 3.06 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" Summary for Subcatchment 6S: Runoff = 0.22 cfs @ 11.89 hrs, Volume= 0.008 af, Depth> 1.87" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 1,530 98 ROOF 790 61 >75% Grass cover, Good, HSG B 2,320 85 Weighted Average 790 Pervious Area 1,530 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 20 0.4000 3.06 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" Summary for Subcatchment 7S: Runoff = 0.38 cfs @ 12.05 hrs, Volume= 0.022 af, Depth> 0.66" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10 YEAR Rainfall=3.50" Area (so CN Description 11,980 60 Woods, Fair, HSG B 1,550 98 DRIVE 770 98 ROAD 2,910 61 >75% Grass cover, Good, HSG B 17,210 65 Weighted Average 14,890 Pervious Area 2,320 Impervious Area POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 8 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.8 100 0.1700 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 1.5 130 0.0800 1.41 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 11.3 230 Total Summary for Reach C: CULVERT Inflow Area = 1.987 ac, 8.32% Impervious, Inflow Depth > 0.35" for 10 YEAR event Inflow = 0.82 cfs @ 12.09 hrs, Volume= 0.058 of Outflow = 0.82 cfs @ 12.10 hrs, Volume= 0.058 af, Atten= 0%, Lag= 0.2 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 4.75 fps, Min. Travel Time= 0.1 min Avg. Velocity = 2.26 fps, Avg. Travel Time= 0.2 min Peak Storage= 5 cf @ 12.09 hrs, Average Depth at Peak Storage= 0.18' Bank-Full Depth= 3.00', Capacity at Bank-Full= 116.34 cfs 36.0" Diameter Pipe, n= 0.012 Length= 27.0' Slope= 0.02597' Inlet Invert= 133.40', Outlet Invert= 132.70' 0 Summary for Pond 1 P: SHALLOW GRASS Inflow Area = 0.587 ac, 21.66% Impervious, Inflow Depth > 0.29" for 10 YEAR event Inflow = 0.38 cfs @ 11.90 hrs, Volume= 0.014 of Outflow = 0.08 cfs @ 12.03 hrs, Volume= 0.014 af, Atten= 79%, Lag= 7.4 min Discarded = 0.08 cfs @ 12.03 hrs, Volume= 0.014 of Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 149.25' @ 12.03 hrs Surf.Area= 706 sf Storage= 159 cf Plug-Flow detention time= 12.1 min calculated for 0.014 of(100% of inflow) Center-of-Mass det. time= 11.7 min ( 819.0 - 807.4 ) Volume Invert Avail.Storage Storage Description #1 149.00' 1,440 cf Custom Stage Data (Prismatic)Listed below (Recalc) POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 ©2007 HydroCAD Software Solutions LLC Page 9 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 149.00 590 0 0 150.00 1,060 825 825 150.50 1,400 615 1,440 Device Routing Invert Outlet Devices #1 Primary 150.00' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 149.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.08 cfs @ 12.03 hrs HW=149.25' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.08 cfs) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=149.00' (Free Discharge) 't--1=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 2P: SHALLOW GRASS Inflow Area = 0.410 ac, 19.56% Impervious, Inflow Depth > 0.80" for 10 YEAR event Inflow = 0.51 cfs @ 12.04 hrs, Volume= 0.027 of Outflow = 0.08 cfs @ 12.48 hrs, Volume= 0.027 af, Atten= 84%, Lag= 26.4 min Discarded = 0.08 cfs @ 12.48 hrs, Volume= 0.027 of Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 163.61' @ 12.48 hrs Surf.Area= 720 sf Storage= 382 cf Plug-Flow detention time= 37.7 min calculated for 0.027 of(100% of inflow) Center-of-Mass det. time= 37.1 min ( 859.3 - 822.2 ) Volume Invert Avail.Storage Storage Description #1 163.00' 1,160 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 163.00 530 0 0 164.00 840 685 685 164.50 1,060 475 1,160 Device Routing Invert Outlet Devices #1 Primary 164.00' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 163.00' 5.000 in/hr Exfiltration over Surface area POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 10 Discarded OutFlow Max=0.08 cfs @ 12.48 hrs HW=163.61' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.08 cfs) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=163.00' (Free Discharge) 't--1=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: SHALLOW GRASS Inflow Area = 2.590 ac, 0.90% Impervious, Inflow Depth > 0.50" for 10 YEAR event Inflow = 1.57 cfs @ 12.08 hrs, Volume= 0.107 of Outflow = 0.17 cfs @ 13.43 hrs, Volume= 0.100 af, Atten= 89%, Lag= 81.0 min Discarded = 0.17 cfs @ 13.43 hrs, Volume= 0.100 of Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 147.47' @ 13.43 hrs Surf.Area= 1,461 sf Storage= 1,711 cf Plug-Flow detention time= 124.3 min calculated for 0.099 of(93% of inflow) Center-of-Mass det. time= 101.5 min ( 945.3 - 843.8 ) Volume Invert Avail.Storage Storage Description #1 146.00' 3,455 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 890 0 0 147.00 1,260 1,075 1,075 148.00 1,690 1,475 2,550 148.50 1,930 905 3,455 Device Routing Invert Outlet Devices #1 Primary 147.50' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 146.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.17 cfs @ 13.43 hrs HW=147.47' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.17 cfs) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=146.00' (Free Discharge) 't--1=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 4P: EAVE TRENCH Inflow Area = 0.035 ac,100.00% Impervious, Inflow Depth > 3.02" for 10 YEAR event Inflow = 0.20 cfs @ 11.89 hrs, Volume= 0.009 of Outflow = 0.03 cfs @ 11.60 hrs, Volume= 0.009 af, Atten= 86%, Lag= 0.0 min Discarded = 0.03 cfs @ 11.60 hrs, Volume= 0.009 of POSTDEVELOPMENT Type 11 24-hr 10 YEAR Rainfall=3.50" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 11 Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 206.30' @ 12.05 hrs Surf.Area= 234 sf Storage= 121 cf Plug-Flow detention time= 25.7 min calculated for 0.009 of(100% of inflow) Center-of-Mass det. time= 25.2 min ( 753.4 - 728.1 ) Volume Invert Avail.Storage Storage Description #1 205.00' 281 cf 3.00'W x 78.00'L x 3.00'H Prismatoid 702 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded 205.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.03 cfs @ 11.60 hrs HW=205.05' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.03 cfs) Summary for Pond 5P: INFILTRATION TRENCH Inflow Area = 0.053 ac, 65.95% Impervious, Inflow Depth > 1.87" for 10 YEAR event Inflow = 0.22 cfs @ 11.89 hrs, Volume= 0.008 of Outflow = 0.03 cfs @ 11.60 hrs, Volume= 0.008 af, Atten= 87%, Lag= 0.0 min Discarded = 0.03 cfs @ 11.60 hrs, Volume= 0.008 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 196.32' @ 12.08 hrs Surf.Area= 234 sf Storage= 123 cf Plug-Flow detention time= 30.1 min calculated for 0.008 of(100% of inflow) Center-of-Mass det. time= 29.9 min ( 804.5 - 774.6 ) Volume Invert Avail.Storage Storage Description #1 195.00' 187 cf 3.00'W x 78.00'L x 2.00'H Prismatoid 468 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded 195.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.03 cfs @ 11.60 hrs HW=195.02' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.03 cfs) Summary for Link D: DESIGN POINT Inflow Area = 4.973 ac, 4.86% Impervious, Inflow Depth > 0.19" for 10 YEAR event Inflow = 1.17 cfs @ 12.08 hrs, Volume= 0.080 of Primary = 1.17 cfs @ 12.08 hrs, Volume= 0.080 af, Atten= 0%, Lag= 0.0 min Primary outflow= Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 12 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: Runoff Area=60,990sf 2.72% Imperious Runoff Depth>0.81" Flow Length=500' Tc=13.9 min CN=61 Runoff=1.49 cfs 0.094 of Subcatchment2S: Runoff Area=112,830 sf 0.90% Imperious Runoff Depth>0.81" Flow Length=770' Tc=13.0 min CN=61 Runoff=2.87 cfs 0.174 of Subcatchment3S: Runoff Area=7,740 sf 26.49% Imperious Runoff Depth>1.39" Flow Length=155' Slope=0.1200 '/' Tc=0.6 min CN=71 Runoff=0.56 cfs 0.021 of Subcatchment4S: Runoff Area=17,840 sf 19.56% Imperious Runoff Depth>1.20" Flow Length=660' Tc=11.0 min CN=68 Runoff=0.78 cfs 0.041 of Subcatchment5S: Runoff Area=1,530 sf 100.00% Imperious Runoff Depth>3.65" Flow Length=20' Slope=0.4000 '/' Tc=0.1 min CN=98 Runoff=0.24 cfs 0.011 of Subcatchment6S: Runoff Area=2,320 sf 65.95% Imperious Runoff Depth>2.46" Flow Length=20' Slope=0.4000 '/' Tc=0.1 min CN=85 Runoff=0.28 cfs 0.011 of Subcatchment7S: Runoff Area=17.210 sf 13.48% Imperious Runoff Depth>1.02" Flow Length=230' Tc=11.3 min CN=65 Runoff=0.62 cfs 0.034 of Reach C: CULVERT Avg. Depth=0.24' Max Vel=5.68 fps Inflow=1.49 cfs 0.094 of D=36.0" n=0.012 L=27.0' S=0.0259 '/' Capacity=116.34 cfs Outflow=1.49 cfs 0.094 of Pond 1P: SHALLOW GRASS Peak Elev=149.41' Storage=278 cf Inflow=0.56 cfs 0.021 of Discarded=0.09 cfs 0.021 of Primary=0.00 cfs 0.000 of Outflow=0.09 cfs 0.021 of Pond 2P: SHALLOW GRASS Peak EIev=164.00' Storage=684 cf Inflow=0.78 cfs 0.041 of Discarded=0.10 cfs 0.041 of Primary=0.00 cfs 0.000 of Outflow=0.10 cfs 0.041 of Pond 3P: SHALLOW GRASS Peak EIev=147.65' Storage=1,991 cf Inflow=2.87 cfs 0.174 of Discarded=0.18 cfs 0.109 of Primary=1.61 cfs 0.045 of Outflow=1.79 cfs 0.154 of Pond 4P: EAVE TRENCH Peak EIev=206.66' Storage=156 cf Inflow=0.24 cfs 0.011 of Outflow=0.03 cfs 0.011 of Pond 5P: INFILTRATION TRENCH Peak EIev=196.91' Storage=179 cf Inflow=0.28 cfs 0.011 of Outflow=0.03 cfs 0.011 of Link D: DESIGN POINT Inflow=2.76 cfs 0.173 of Primary=2.76 cfs 0.173 of Total Runoff Area = 5.061 ac Runoff Volume = 0.385 of Average Runoff Depth = 0.91" 93.84% Pervious = 4.749 ac 6.16% Impervious = 0.312 ac POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment 1S: Runoff = 1.49 cfs @ 12.08 hrs, Volume= 0.094 af, Depth> 0.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 43,310 60 Woods, Fair, HSG B 1,330 98 DRIVE 330 98 ROAD 16,020 61 >75% Grass cover, Good, HSG B 60,990 61 Weighted Average 59,330 Pervious Area 1,660 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.1600 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 3.8 400 0.1200 1.73 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 13.9 500 Total Summary for Subcatchment 2S: Runoff = 2.87 cfs @ 12.07 hrs, Volume= 0.174 af, Depth> 0.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 92,090 60 Woods, Fair, HSG B 1,010 98 DRIVE 19,730 61 >75% Grass cover, Good, HSG B 112,830 61 Weighted Average 111,820 Pervious Area 1,010 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 3.8 470 0.1700 2.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.3 200 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 13.0 770 Total POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment 3S: Runoff = 0.56 cfs @ 11.90 hrs, Volume= 0.021 af, Depth> 1.39" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 2,050 98 DRIVE 1,210 60 Woods, Fair, HSG B 4,480 61 >75% Grass cover, Good, HSG B 7,740 71 Weighted Average 5,690 Pervious Area 2,050 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 75 0.1200 2.47 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" 0.1 80 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 0.6 155 Total Summary for Subcatchment 4S: Runoff = 0.78 cfs @ 12.04 hrs, Volume= 0.041 af, Depth> 1.20" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 5,890 60 Woods, Fair, HSG B 3,490 98 DRIVE 8,460 61 >75% Grass cover, Good, HSG B 17,840 68 Weighted Average 14,350 Pervious Area 3,490 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.9 100 0.2200 0.19 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 1.7 240 0.2100 2.29 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.4 320 0.1200 12.41 49.66 Channel Flow, Area= 4.0 sf Perim= 6.5' r= 0.62' n= 0.030 Earth, grassed &winding 11.0 660 Total POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment 5S: Runoff = 0.24 cfs @ 11.89 hrs, Volume= 0.011 af, Depth> 3.65" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 1,530 98 ROOF 1,530 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 20 0.4000 3.06 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" Summary for Subcatchment 6S: Runoff = 0.28 cfs @ 11.89 hrs, Volume= 0.011 af, Depth> 2.46" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 1,530 98 ROOF 790 61 >75% Grass cover, Good, HSG B 2,320 85 Weighted Average 790 Pervious Area 1,530 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 20 0.4000 3.06 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" Summary for Subcatchment 7S: Runoff = 0.62 cfs @ 12.04 hrs, Volume= 0.034 af, Depth> 1.02" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 25 YEAR Rainfall=4.20" Area (so CN Description 11,980 60 Woods, Fair, HSG B 1,550 98 DRIVE 770 98 ROAD 2,910 61 >75% Grass cover, Good, HSG B 17,210 65 Weighted Average 14,890 Pervious Area 2,320 Impervious Area POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 16 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.8 100 0.1700 0.17 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.75" 1.5 130 0.0800 1.41 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 11.3 230 Total Summary for Reach C: CULVERT Inflow Area = 1.987 ac, 8.32% Impervious, Inflow Depth > 0.57" for 25 YEAR event Inflow = 1.49 cfs @ 12.08 hrs, Volume= 0.094 of Outflow = 1.49 cfs @ 12.08 hrs, Volume= 0.094 af, Atten= 0%, Lag= 0.2 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 5.68 fps, Min. Travel Time= 0.1 min Avg. Velocity = 2.52 fps, Avg. Travel Time= 0.2 min Peak Storage= 7 cf @ 12.08 hrs, Average Depth at Peak Storage= 0.24' Bank-Full Depth= 3.00', Capacity at Bank-Full= 116.34 cfs 36.0" Diameter Pipe, n= 0.012 Length= 27.0' Slope= 0.02597' Inlet Invert= 133.40', Outlet Invert= 132.70' 0 Summary for Pond 1 P: SHALLOW GRASS Inflow Area = 0.587 ac, 21.66% Impervious, Inflow Depth > 0.42" for 25 YEAR event Inflow = 0.56 cfs @ 11.90 hrs, Volume= 0.021 of Outflow = 0.09 cfs @ 12.06 hrs, Volume= 0.021 af, Atten= 84%, Lag= 9.4 min Discarded = 0.09 cfs @ 12.06 hrs, Volume= 0.021 of Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 149.41' @ 12.06 hrs Surf.Area= 781 sf Storage= 278 cf Plug-Flow detention time= 21.6 min calculated for 0.021 of(100% of inflow) Center-of-Mass det. time= 21.3 min ( 820.5 - 799.3 ) Volume Invert Avail.Storage Storage Description #1 149.00' 1,440 cf Custom Stage Data (Prismatic)Listed below (Recalc) POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 ©2007 HydroCAD Software Solutions LLC Page 17 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 149.00 590 0 0 150.00 1,060 825 825 150.50 1,400 615 1,440 Device Routing Invert Outlet Devices #1 Primary 150.00' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 149.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.09 cfs @ 12.06 hrs HW=149.41' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.09 cfs) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=149.00' (Free Discharge) 't--1=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 2P: SHALLOW GRASS Inflow Area = 0.410 ac, 19.56% Impervious, Inflow Depth > 1.20" for 25 YEAR event Inflow = 0.78 cfs @ 12.04 hrs, Volume= 0.041 of Outflow = 0.10 cfs @ 12.59 hrs, Volume= 0.041 af, Atten= 87%, Lag= 32.8 min Discarded = 0.10 cfs @ 12.59 hrs, Volume= 0.041 of Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 164.00' @ 12.59 hrs Surf.Area= 840 sf Storage= 684 cf Plug-Flow detention time= 66.2 min calculated for 0.041 of(100% of inflow) Center-of-Mass det. time= 65.8 min ( 879.1 - 813.3 ) Volume Invert Avail.Storage Storage Description #1 163.00' 1,160 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 163.00 530 0 0 164.00 840 685 685 164.50 1,060 475 1,160 Device Routing Invert Outlet Devices #1 Primary 164.00' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 163.00' 5.000 in/hr Exfiltration over Surface area POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 18 Discarded OutFlow Max=0.10 cfs @ 12.59 hrs HW=164.00' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.10 cfs) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=163.00' (Free Discharge) 't--1=Broad-Crested Rectangular Weir( Controls 0.00 cfs) Summary for Pond 3P: SHALLOW GRASS Inflow Area = 2.590 ac, 0.90% Impervious, Inflow Depth > 0.81" for 25 YEAR event Inflow = 2.87 cfs @ 12.07 hrs, Volume= 0.174 of Outflow = 1.79 cfs @ 12.21 hrs, Volume= 0.154 af, Atten= 38%, Lag= 8.7 min Discarded = 0.18 cfs @ 12.21 hrs, Volume= 0.109 of Primary = 1.61 cfs @ 12.21 hrs, Volume= 0.045 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 147.65' @ 12.21 hrs Surf.Area= 1,541 sf Storage= 1,991 cf Plug-Flow detention time= 98.1 min calculated for 0.154 of(88% of inflow) Center-of-Mass det. time= 61.4 min ( 892.2 - 830.8 ) Volume Invert Avail.Storage Storage Description #1 146.00' 3,455 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 890 0 0 147.00 1,260 1,075 1,075 148.00 1,690 1,475 2,550 148.50 1,930 905 3,455 Device Routing Invert Outlet Devices #1 Primary 147.50' 10.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #2 Discarded 146.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.18 cfs @ 12.21 hrs HW=147.64' (Free Discharge) L2=Exfiltration (Exfiltration Controls 0.18 cfs) Primary OutFlow Max=1.47 cfs @ 12.21 hrs HW=147.64' (Free Discharge) L1=Broad-Crested Rectangular Weir(Weir Controls 1.47 cfs @ 1.02 fps) Summary for Pond 4P: EAVE TRENCH Inflow Area = 0.035 ac,100.00% Impervious, Inflow Depth > 3.65" for 25 YEAR event Inflow = 0.24 cfs @ 11.89 hrs, Volume= 0.011 of Outflow = 0.03 cfs @ 11.60 hrs, Volume= 0.011 af, Atten= 89%, Lag= 0.0 min Discarded = 0.03 cfs @ 11.60 hrs, Volume= 0.011 of POSTDEVELOPMENT Type 11 24-hr 25 YEAR Rainfall=4.20" Prepared by {enter your company name here} Printed 9/14/2016 HydroCAD®8.50 s/n 000476 @2007 HydroCAD Software Solutions LLC Page 19 Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 206.66' @ 12.08 hrs Surf.Area= 234 sf Storage= 156 cf Plug-Flow detention time= 34.7 min calculated for 0.011 of(100% of inflow) Center-of-Mass det. time= 34.2 min ( 761.1 - 726.8 ) Volume Invert Avail.Storage Storage Description #1 205.00' 281 cf 3.00'W x 78.00'L x 3.00'H Prismatoid 702 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded 205.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.03 cfs @ 11.60 hrs HW=205.06' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.03 cfs) Summary for Pond 5P: INFILTRATION TRENCH Inflow Area = 0.053 ac, 65.95% Impervious, Inflow Depth > 2.46" for 25 YEAR event Inflow = 0.28 cfs @ 11.89 hrs, Volume= 0.011 of Outflow = 0.03 cfs @ 11.60 hrs, Volume= 0.011 af, Atten= 90%, Lag= 0.0 min Discarded = 0.03 cfs @ 11.60 hrs, Volume= 0.011 of Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 196.91' @ 12.25 hrs Surf.Area= 234 sf Storage= 179 cf Plug-Flow detention time= 47.3 min calculated for 0.011 of(100% of inflow) Center-of-Mass det. time= 47.0 min ( 815.5 - 768.5 ) Volume Invert Avail.Storage Storage Description #1 195.00' 187 cf 3.00'W x 78.00'L x 2.00'H Prismatoid 468 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded 195.00' 5.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.03 cfs @ 11.60 hrs HW=195.04' (Free Discharge) L1=Exfiltration (Exfiltration Controls 0.03 cfs) Summary for Link D: DESIGN POINT Inflow Area = 4.973 ac, 4.86% Impervious, Inflow Depth > 0.42" for 25 YEAR event Inflow = 2.76 cfs @ 12.20 hrs, Volume= 0.173 of Primary = 2.76 cfs @ 12.20 hrs, Volume= 0.173 af, Atten= 0%, Lag= 0.0 min Primary outflow= Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs